removed reference to button color and gradient

Changed the wording to reflect the default button's new look since it's no longer grey and doesn't have a gradient. I'd say this new wording isn't ideal and needs something a bit more, well, descriptive.
removed extraneous space
remove .btn-group

The example doesn't use .btn-group and adding the class causes "bad things to happen," as the saying goes.

http://jsfiddle.net/josephtate/g6AWF
Another case for Issue #10099

Another case for Issue #10099
Merge pull request #10103 from hero-m/patch-1

Another case for Issue #10099
turn some buttons into <button> elements where possible
Merge branch 'master' of github.com:twbs/bootstrap
forgot a pair of buttons
Add role="button" to <a> buttons

These should really be <button> elements, but until that gets squared away, this will suffice.
Add even more  role="button" attributes

Missed the <a class="btw" in my regex search
Merge pull request #9996 from jodytate/master

changed description of default button
grunt dist on glyphicons width change
Merge pull request #10112 from kevinSuttle/button-roles

Add role="button" to <a> buttons
fixes #9887: documents show and hide classes
Merge branch 'master' of github.com:twbs/bootstrap
update raw files (should fix builds)
Fixes #9008: remove `alert-block` class from example
Merge pull request #10128 from leoj3n/alert-block-remove

Fixes #9008: remove `alert-block` class from example